RNA was the first informational polymer

The emergence of genetic replication coincided with the formation of the first RNA molecules.

Another polymer preceded RNA

Information transfer and genetic replication existed in molecules before RNA.
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Tyler Roche   Subscribe ...


Building Block Selection


Ribonucleotides can form through selective prebiotic pathways.

eThere is a prebiotically plausible pathway from building blocks to ribonucleotides.


The phosphate linkage is far from the easiest ionic linkage that could have evolved on the early Earth.

eOrganic acids could have provided a more facile and reversible linkage than phosphate in proto-nucleic acid systems.


RNA’s components can be selectively “picked” from the pool of possible prebiotic monomers

eRibose can be prebiotically selected from a mix of complicated sugars.


Noncanonical nucleic acids could have formed more easily than canonical nucleic acids on the early Earth.

eNoncanonical nucleobases react with sugars.

eThere are plausible prebiotic routes to non-sugar nucleic acids.

Polymeric selection


RNA would have been the preferred molecule for polymerization when compared to potential alternatives.

eNonenzymatic primer extension with activated ribonucleotides is more efficient than the same with activated arabinonucleotides.


Noncanonical nucleosides provide a more favorable scaffold for oligomerization than canonical nucleosides.

eNoncanonical nucleobases self-assemble into hexad structures.


It would have been too difficult to transition from an RNA-only world to the RNA-DNA world life uses today.

eNucleic acid chimeras are less stable than the corresponding homopolymers.


RNA could have been a fully sufficient molecule on the early Earth, with both catalytic and informational functions.

eRNA has catalytic functionality in addition to itso informational functionality.


RNA’s base pairing abilities are perfect for the initial genetic polymer and needed no other precedent.

eRNA has optimal base-pairing strength for its function.